Oxidation process



Patented Apr. 14, 1931 UNITED STATES PATENT-OFFICE FRED SCHOLEFIELD, 01 WALKIDEN, ENGLAND, ASSIGNOR TO THE MANCHESTER OXIDE COMPANY LIMITED, OF MANCHESTER, ENGLAND OXIDATION raocnss No Drawing. Application filed June 27, 1928, Serial No. 288,815 and indGreat Britain August 4, 1927.

This invention relates to improvements in oxidation processes in the dyeing or printing of textiles.

I have found that carbonylferrocyanides 5 of the alkali metals, or alkaline earth metals have considerable catalytic or oxygen carrying properties, and can be employed to give catalytic or oxygen carrying effects in oxidation processes in the dyeing or printing of 1 textiles.

In the dyeing and printing of aniline blacks on fabrics, by what is known as the prussiate process, an oxidizing mater al such as potassium chlorate together wlth sodium or potassium prussiate (ferrocyanide) has been mixed with the aniline salt.

The exact function of the prussiate is not known with certainty, but is usually considered to be of a catalytic or oxygen carrying nature. I have found however that if a carbonylferrocyanide is used instead of the prussiate, and, for this purpose we use sodlum carbonylferrocyanide, although carbonylferrocyanides of the other alkalin metals, or alkaline earth metals may also be used, that advantages result, excellent aniline blacks being obtained on the fabric with greater certainty of control.

The following example in which the parts are given by weight illustrates the use of sodium carbonylferrocyanide in the dyeing of aniline'black on fabrics, the sodium carbonylferrocyanide being employed instead of the usual prussiate.

The following solutions are prepared (a) A solution of 'parts of aniline salt in 200 parts of water;

(6) A solution of 35 parts of sodium chlorate in 400 parts of water; and

(be) A solution of 30 to 40 parts of sodium car onylferrocyanide in 250 parts of water.

When the solutions are quite cold they are mixed together. The cotton fabric to be dyed is padded through the mixed solutions, dried at a low temperature, steamed at a temperatureof (land chromed 111 a 0.5% solution of bichromate of soda at a temperature of 50 C. The fabric is then well washed, soaped and dried.

In the chlorate discharge of such colors as usually carried out, the

obtained, a result not hitherto generally obtainable. y

The following example in which the parts are given by weight illustrates the use of sodium carbonylferrocyanide in the chlorate discharge of indigo the sodium carbonylferrocyanide being employed in the place of the usual p1ussiate:-

200 parts British gum powder, 60 parts water, 550 parts chlorate of alumina (Sp. G. 42 Tw.) and 150 parts soduim chlorate are mixed togetherand boiled and after the mixture has been allowed to cool 30 to 10 parts sodium carbonylferrocyanide are added. The discharge paste thus formed is employed for the chlorate discharge of dark indigo dyed fabric being printed thereon in the usual way after which the fabric is dried and steamedfor about 3 minutes in dry steam at a temperature of C. y l The cloth is then washed in water for five minutes at a temperature of between 60 to 80 C., passed through a caustic soda solution (4 Tw.) washed and dried.

F I find that the use of carbonylferrocyanide to give catalytic or oxygen carrying effects in oxidation processes for textile purposes has 7 an advantage over the use of prussiate, on the vbefore printing the discharge paste,

for discharge effects, may be kept longer I risk of the production of poor whites. On

the other hand it has greater activity at temperatures approximating to 100 C. I have also found that when using carbonylferrocyanides there is less tendering of with said: mixture, dried at a low temperature the fabric.

What I claim as my invention and toprotect by Letters Patent is 1. A processfor the production of aniline black on textile fibres in which a solution of an aniline salt, a solution of sodium chlorate and a solution of carbonylferrocyanide are I mixed together andthe fabric treated therewith. r V L .2. Aprocess for the production of aniline black on textile fibres in which a solution of an aniline salt, asolution of sodium chlorate anda solution of a carbonylferrocyanide of an alkali metal are mixed together and the fabric treated therewith. V v

' 3. A process for the production of aniline black on textile fibres in which a solution of an aniline salt, a solution of sodium chlorate and a solution of sodium carbonylferrocyanide are mixed together and the fabric treated therewith.

4. A process for textile fabrics in which a solution of an aniline salt, a. solution ofsodium chlorate and a solution of sodium carbonylferrocyanide.

are mixed together, the fabric impregnated and steamed. r,

'5. A process for dyeing of aniline black on textile fabrics in which a solutionof an aniline salt, a solution of sodium chlorate and a solution ofsodium carbonylferrocy+ anide are mixed together,ythe'fabric impregnated with said mixture, dried at'a low temperature, steamed and chromed. r I a 6. A process for dyeing of aniline black on textile fabrics in which a solutionof an aniline salt, a solution ofsodium chlorate'and a solution of sodium carbonylferrocyanide r are mixed together, thefabric impregnated with said mixture, dried at a lowtemperature, steamed, chromed, washed, soaped and dr ed v, H r p Intestimony whereof Ihave hereunto set my hand. 7 x i a FRED-SCHOLEFIELD without desire dyeing of anilineblack I 

